Novel magnesium-copper hybrid nanomaterials for management of bacterial spot of tomato

Bacterial spot of tomato (BST), predominantly caused by Xanthomonas perforans (Xp) in Florida, is one of the most devastating diseases in hot, humid environments. Bacterial resistance to copper-based bactericides and antibiotics makes disease management extremely challenging. This necessitates alternative solutions to manage the disease. In this study, we used two novel hybrid copper and magnesium nanomaterials noted as magnesium double-coated (Mg-Db) and magnesium-copper (Mg-Cu), to manage BST. In in vitro experiments, no viable cells were recovered following 4 h exposure to 500 µg/ml of both Mg-Db and Mg-Cu, while 100 and 200 µg/ml required 24 h of exposure for complete inhibition. In viability assay using live/dead cell straining method and epifluorescence microscopy, copper tolerant Xp cells were killed within 4 h by both Mg-Cu and Mg-Db nanomaterials at 500 µg/ml, but not by copper hydroxide (Kocide 3000). In the greenhouse, Mg-Db and Mg-Cu at 100-500 µg/ml significantly reduced BST severity compared to micron-sized commercial Cu bactericide Kocide 3000 and the growers' standard (copper hydroxide + mancozeb) (P < 0.05). In field studies, Mg-Db and Mg-Cu nanomaterials significantly reduced disease severity in two out for field trials. Mg-Db at 500 µg/ml reduced BST severity by 34% compared to the non-treated control without affecting yield in Fall, 2020. The use of hybrid nanomaterials at the highest concentrations (500 µg/ml) used in the field experiments can reduce copper use by 90% compared to the growers' standard. In addition, there was no phytotoxicity observed with the use of hybrid nanomaterials in the field. These results suggest the potential of novel magnesium-copper based hybrid nanomaterials to manage copper-tolerant bacterial pathogens.

Early identification of patient at risk of acute severe pancreatitis with systemic inflammatory response

Introduction and Objective: Clinically, the Systemic Inflammatory Response Syndrome (SIRS) is identified by two or more symptoms including fever or hypothermia, tachycardia, tachypnoea and change in blood leukocyte count. The relationship between SIRS symptoms at the time of presentation and severity of pancreatitis is yet to be determined though progression of SIRS in subsequent days has been already correlated. The aim our study was to determine the severity of pancreatitis with SIRS score at the time of admission.Materials and Methods: We conducted prospective cohort study of consecutive patient admitted to emergency of KMCTH, with diagnosis of Acute Pancreatitis (AP) from December 2014 to January 2016. Clinical, biochemical and imaging data from the patients were collected to diagnose pancreatitis. Acute Pancreatitis was diagnosed as per Revised Atlanta Classification 2012. SIRS was evaluated at the time of admission and was correlated with Modified Marshall scoring system for organ dysfunction and sensitivity, specificity and predictive value of SIRS score at admission for organ failure was calculated.Results: Among 41 patients admitted with diagnosis of Acute pancreatitis irrespective of cause the sensitivity of SIRS score at admission in predicting Severe pancreatitis was 28 %, specificity was 80%, Positive predictive value was 60 % and NPV was 51 %, with P value of 0.52 and odds ratio of 1.6 ( CI- 0.376-6.808).Conclusion: This study showed that SIRS score at admission is not sensitive in predicting severe pancreatitis however it is specific for severe pancreatitis.

Pre-operative Prediction of Difficult Laparoscopic Cholecystectomy

INTRODUCTION

Laparoscopic cholecystectomy is one of the most common operation performed. Though LC have become safer and easier at times it can be difficult. Difficult cases can result in prolonged operative time, bleeding, bile spillage, conversion to open technique and bile duct injury resulting in unplanned prolonged hospital stay, increase in estimated cost to the patients and for the surgeon it leads to increased stress during operation and time pressure to complete the operative list. . Identification of difficult cases has potential advantages for surgeons, patients and their relatives. We aim to develop and validate a scoring system to predict difficult LC preoperatively.

METHODS

Prospective study. History, physical examination, abdominal ultrasound and biochemical parameters were included to develop a scoring system. Hundred patients undergoing LC were included and preoperative scores were calculated preoperatively to predict difficult LC which was compared with operative assessment.

RESULTS

Sensitivity and specificity of the preoperative scoring for difficult case was 53.8 % and 89.2 % respectively with PPV of 63.64 % and NPV of 84.62%. Only three parameters (history of acute cholecystitis, gall bladder wall thickness and contracted gall bladder) were statistically significant to predict difficult LC individually. Area under ROC curve was 0.779 (95 % CI, 0.657-0.883).

CONCLUSIONS

Preoperative scoring system can be used to predict difficult LC. Surgeons can plan operation based on predicted difficulty. Patients and relatives can be counselled preoperatively for the possibility of difficult operation, prolonged hospital stay and increased cost in predicted difficult case.

Prevalence of pancreaticobiliary reflux in symptomatic cholelithiasis and its significance

Aims: Pancreaticobiliary reflux (PBR) is reflux of pancreatic enzymes into the biliary tree which occurs as a result of an anamoly of pancreaticobiliary junction (PBJ) or functionally impaired sphincter. PBR is associated with changes in biliary epithelium and is known to cause benign and malignant biliary pathology. Various authors have reported prevalence of PBR in patients with normal PBJ ranging from 20 % to 83.5 %. With aim to detect the prevalence of PBR in patients with symptomatic cholelithiasis in Nepalese population we conducted this study. Materials and methods: Thirty patients undergoing elective laparoscopic cholecystectomy (LC) for symptomatic cholelithiasis were included in the study. History, physical findings and relevant investigations including liver function test, serum amylase and abdominal ultrasound were recorded. Bile sample for amylase was taken from gall bladder during LC percuatneously before manipulation of calot’s triangle and common bile duct. Bile amylase level above serum amylase level was considered positive for PBR. Results: Mean age of the patient was 37.27 (± 14.41) years. Out of 30, 6 (20 %) patients were male and 24 (80 %) were female. Mean BMI was 21.58 (± 3.2). PBR reflux was present in 66.7 % of patients out of which 2 were male and 18 were female that was not statistically significant (p = 1.41) when compared with patients without PBR. Conclusion: PBR occurs in patient with cholelithiasis and has role in pathogenesis of gallstones disease and gall bladder carcinoma. Long term surveillance would be required to ascertain the significance of detection of PBR after LC. Journal of College of Medical Sciences-Nepal, 2013, Vol-9, No-1, 1-6 DOI: http://dx.doi.org/10.3126/jcmsn.v9i1.9666